With the increasing maturity of digital television technology, traditional analog television is translated to digital television on a large scale. During the translation, operators put forward various demands according to their own strategies. For example, to restrict watching ranges of some subscribers or adopt different charge standards in different areas, some programs are needed to be hidden from the subscribers, i.e., the subscribers are forbidden to watch these programs.
At present, there is a program hiding solution based on an authorization mechanism. In the solution, an efficient mechanism for charging is implemented by authorizing programs for each subscriber. A subscriber can only watch authorized programs. Although unauthorized programs may be searched for and stored, they can only be watched normally after these programs are paid and authorized. Therefore, through such solution, the subscribers may know the existence of the programs, but they need to pay to watch them.
If the television station does not desire that particular subscribers be aware of the existence of some special programs, the solution described above does not meet the requirements. Additionally, if the programs are required to be hidden from many subscribers in one group, each subscriber is required to be authorized through the solution, thus it is comparatively cumbersome to implement.